Scraper



Aug 5, 1941.

H. H. WASHBOND SGRAPER Filed Aug. 1, 1938 e Sheets-Sheet 2 Aug 5, 1941.

H. H. WASHBOND SCRAPER Filed Aug. 1, 1938 6 Sheets-Sheet 5 Aug 1941- H. H. WASHBOND 7 2,251,307

SCRAPER Filed Aug. 1, 1938 6 Sheets-Sheet 4 fiheey H u hsmeozyo.

Aug 5, 1941. H. H. WASHBOND SCRAPER e Sheets-Sheet 5 Filed Aug. 1, 1938 a m M u n m y 4 m m tttmmtttmtcttctfimtttttmttfitmm w W Patented Aug. 5, 1941 SCEAPER Harry H. Washbond, Springfield, Ill., assignor to Baker Manufacturing 00., Springfield, 111., a. corporation of Illinois Application August 1, 1938, Serial No. 222,323

28 Claims.

This invention relates to scrapers of the type having a bowl or dirt receivirig receptacle" pivotally supported from a frame.

More specifically the invention relates to wagon scrapers having means for lowering the rear end of the scra er bowl or dirt receptacle as the front end of the bowl or receptacle is lowered into scraping or digging position.

Scraper bowls or dirt receptacles of wagon scrapers have heretofore been pivotally supported by a main frame which is held in spaced relation from the ground. Therefore, when the front end of the scrape-r bowl or dirt receptacle is lowered to a scraping position so that the scraper blade can cut into the ground, the bottom of the bowl or receptacle is appreciably tilted. The amount of tilt, of course, depends upon the depth of cut to be made by the scraper blade and also upon the height of the bottom of the scraper bowl from the ground when the bowl is blade and to fall out of the front end of the bowl.

According to this invention, scraper bowls or dirt receptacles are mounted on their supporting frames through an extensible medium. Means are provided to automatically shorten this medium for lowering the entire bottom of the scraper bowl when the scraper blade carried thereby is lowered into scraping position.

When the front end of the bowl is raised from scraping position above the ground level, the automatic means operate to lengthen or permit the lengthening of the extensible medium for raising the entire length of the scraper bowl. A desired clearance between the bottom of the bow, and the ground level is thus obtained for load carrying operations.

According to this invention the extensible means may take the form of springs, fluid pressure operated jacks or other devices adapted to vary in height. The springs, jacks or the like are automatically operated by the means for tilting the scraper bowl.

One of the features of this invention is the provision of a vertically movable rear end memher or gate supported through springs or jacks from the main frame of the device. This rear end member pivotally carries the scraper bowl and also form's a closure for the rear end of the bowl. When the bowl is tilted to dumping position, the bottom rear end of the bowl is moved away from the member so that the contents of the bowl are discharged by gravity beneath the member which can then function to level oil the discharged load.

The bowl or dirt receptacle is preferably tilted relative to the main frame by a pair of fluid pressure operated jacks acting between each side of the scraper bowl and the main frame. These jacks are in fluid intercommunication so as to exert equal forces against both sides: of the scraper bowl. Fluid is applicable to either end of both jack cylinders from a single valve on the pulling vehicle for the scraper.

Since the jacks are in fluid intercommunication, the scraper blade in scraping position will be held level even though the main frame is tilted. Thus if a wheel on one side of the main frame drops into a hole or rut, the main frame will naturally tilt, tending to carry the blade into the same tilt. This will either produce a greater pressure in the lower end of the jack on the low side 'of the frame because the ground will resist the increased cut taken by the low end of the blade or will produce a greater pressurein the upper end of the jack due to the scraper blade being pulled further into the ground. In either event, fluid will flow between the jacks until pressures in the jacks are equalized. Such equalization of pressures will cause a change in the rela tive positions of the pistons in the two jacks.

Since the bowl is supported from the main frame on a vertically movable member, this member can level olf the bowl even though the frame is tilted. The bowl is not twisted or cooked as in the case of a bowl directly pivoted to the main frame.

It is, then, an object of this invention to provide a scraper having a dirt-receiving receptacle mounted on vertically movable pivots that are automatically lowered as the receptacle is tilted into scraping or cutting position and that are automatically raised as the receptacle is moved to a load-carrying position.

A further object of this invention is to support scraper bowls from the main frame of a scraper through an extensible medium.

A further object of the invention is to provide a scraper having a vertically movable rear end member carrying the scraper bowl and acting as a rear end gate for the bowl.

A further object of the invention is to provide a two-wheeled wagon scraper with a pivotally mounted dirt receptacle that is adapted to settle or move toward the ground when tilted into scraping position.

A further object of the invention is to maintain the bottoms of scraper bowls in a nearly horizontal position during scraping operations and at the same time to provide clearance between the bottoms of the scraper bowls and the ground level during load-carrying positions.

Another object of the invention is to provide a wagon scraper having a pivotally mounted open ended dirt receptacle that is wider at the rear end than at the front end thereof.

Other and further objects of the invention will become apparent to those skilled in the art from the following detailed description of the annexed sheets of drawings which disclose preferred embodiments of the invention.

On the drawings:

Figure 1 is a side elevational view of a wheeled scraper according to this invention.-

Figure 2 is a top plan view of the scraper shown in Figure 1.

Figure 3 is a vertical cross-sectional view taken along the line IIIIII of Figure 2 and illustrating in dotted lines the scraper bowl in dumping position.

Figure 4 is a vertical cross-sectional view taken along the line IV-IV of Figure 2 and illustrating in dotted lines the scraper bowl in scraping position.

Figure 5 is a rear end elevational View of the scraper shown in Figures 1 to 4 inclusive, with parts of the wheels broken away.

Figure 6 is avertical cross-sectional view taken along the line VI-VI of Figure 5.

Figure 7 is a vertical cross-sectional view, with parts shown in elevation, taken along the line VII-VII of Figure 6.

Figure 8 is a side elevational view, with parts broken away and shown in vertical cross section, of a modified scraper according to this invention.

Figure 9 is a fragmentary rear end elevational view of the scraper shown in Figure 8.

Figure 10 is an enlarged vertical cross-sectional view, with parts shown in elevation, of a valve for operating the jacks shown in Figures 8 and 9.

As shown on the drawings:

In Figures 1 to 4 inclusive, the reference numeral IE) designates generally the main frame of the scraper. The main frame Ill comprises a tongue member ll having a coupling I 2 at the front end thereof for attachment to a prime mover such as atractor. The tongue II is secured, as by welding, to a transverse front beam 13 at the center of the beam.

Side frame beams M are secured at their front ends to the ends of the transverse front beam [3. The side frame beams M are in spaced parallel relation.

The frame I5 is supported from the ground by means of wheels I5. The wheels I5 are rotatably carried on axle structures l6 including attachment plates I! which are bolted onto the side frame beams M by means of bolts such as 18.

The attachment plates I! have a plurality of rows of bolt-receiving holes therethrough in spaced vertical relation as best shown in Figure 1. Selection of a desired row of holes for receiving the bolts l8 therethrough will space the frame [4 a desired distance from the ground. If desired, the side frame beams Hi can carry a plurality of bolt-receiving means along the length thereof so that the position of the wheels 15 can be varied along the side frame beams M.

The axle structure and mounting means used on the scrapers of this invention are more fully described and claimed in the copending application of Jacob S. Walch, Serial 130,655, filed March 13, 1937.

The rear ends of the side frame beams I carry vertical posts I9. These posts l9 are preferably integrally connected with the side beams M as by welding and preferably extend a slight distance below the side frame beams as shown at la in Figure 1.

A strong, rigid shaft 20 extends between the side frame beams l4 and is secured at its ends in the portion I 9a of the posts l9. A beam or other supporting member could obviously be used in place of the shaft 20.

As shown in Figures 1 to '7 inclusive, the reference numeral 2! designates generally a transverse frame member or gate between the side frame beams l4 supported on helical springs 22 from the transverse shaft 20.

The frame member 2! comprises a top beam 23, a bottom beam 24 and side plates 25 connecting the beams and extending forwardly between the side frame beams !4. An arcuate plate 26 extends over the front ends of the beams 23 and 24 and defines an arcuate rear wall for the scraper.

Reinforcing rib plates 21 extend from the top beam 23 in spaced parallel relation from the side plates 25 and in back of the arcuate plate 26.

Front and rear spacer plates 28 and 29 (Figures 4 and 6) are mounted between the plates 25 and 21 near the bottoms thereof and are provided with bosses 3!) receiving bolts 3| there-.

through for securing the spacer plates to the plates 25 and 21 as shown in Figure 5.

As best shown in Figures 5, 6 and 7, the bottom bosses 30 of the plates 28 and 29 carry straps 32 extending around the under side of the shaft 29.

The plates 25 and 2'! are cut away as at 33 between the plates 28 and 29 so that the frame 2! can move in a vertical direction relative to the shaft 25. I

Collars 20a are formed on the shaft 20 adjacent to the side plates 25 of the frame 2| for holding the frame 2i in alignment between the side frame beams M.

Additional reinforcing plates 34 and 35 (Figures 3 and 5) extend between the beams 23 and 24 in back of the arcuate plate 25 for rigidifying the central portion of this plate.

The tops of the side plates 25 carry vertical track members 35 defining T-shaped slots for rollers or slides 31. The rollers or slides 31 are supported on shafts 38 from the tops of the posts l9. This slide and track arrangement holds the frame member 2| in vertical position.

As best shown in Figures 5 and '7, the shaft 20 carries saddles 4!] on the top side thereof. Bolts 4! are rotatably mounted in the saddles 40.

As best shown in Figure '7, the bolts such as 6| are threaded through bosses 42 mounted in vertical pipes 43. These bosses 42 have discs 44 secured to the lower ends thereof. The discs 44 abut the lower ends of the pipes 43 and support the springs 22. A rotation of the bolts 4! will serve to raise or lower the pipes 43.

As shown in Figure '7, the pipes 43 are of materially less diameter than the inside diameter of the helical springs 22. In order to prevent the spring from buckling when the same are top beam 23 of the frame 2! in "free slidable relation thereto.

Caps lt (Figures 2, '5 and '7) are bolted t'o the top of the beam 23 around the pipes and rods. These caps it act as abutment plates for the tops of the springs 22 and have square holes therethrough 'to hold the pipes 13 against rotation.

From the above description it should be un'ders'tood that the frame member 21 is supported on the springs '22 from the shaft M of the main frame. This frarn'e'memb'er "2! is therefore Vertically movable as the springs 22 are compressed and released. While four springs have been shown it should be understood that any number can be used. I

As pointed out above, the side plates 25 "of the frame member 21 extend forwardly between the sides frame beams "M. As best show'nin Figure l, the forward extensions of the plates 25 are reinforced by means of beams "41 and is welded to the outer faces of the plates.

As best shown in Figure 2 the forward ends of the plates 25 receivepivotpins or bolts 49 secured to a scraper bowl E) mounted between the side frame beams. The scraper bowl 5!) is thus pivotally supported from the main frame l'il through the vertically movable frame 21.

The scraper bowl Eli is open ended and converges toward the front end as best shown in Figure 2 so that the rear end of -the bowl is wider than the front end. This prevents packing of scraped material in the bowl.

The side walls of the scraper bowl have reinforcing beams 5| welded thereon and the pivot pins 49 are preferably anchored to these reinforcing beams 5l.

As best shown in Figures 3, 4 and '6, the rear ends of the side plates of the bowl 56 are curved as at 52 to conform with the curvature of the arcuate plate 23 of the frame member 2 l.

The bowl 50 has a bottom 53 (Figures 3 and 4) turned up as at 53a at the rear end thereof and turned down as at 531) at the front end thereof.

The rear end sea of the bottom 53 is disposed within the limits of the plate 26 during scraping and load-carrying positions of the bowl 5!). However, when the bowl is tilted into dumping position as shown in dotted lines in Figure 3, this rear end portion 53a is moved forwardly from the bottom of the plate so that dirt can fall by gravity out of the opening between the bowl bottom and plate 26. The beam 24 will level off the discharged dirt as the scraper is pulled forwardly.

The front end portion 53b of the bottom receives a scraper blade 54 thereon. This blade 5% is turned up at the ends as at 54a and is secured to the side walls of the bowl. If desired separate angle members or corner reinforcing members can be used with one leg thereof secured to the blade and the other leg thereof secured to the adjacent side wall of the bowl.

A reinforcing member 55 is mounted under the turned-down portion 53b of the bottom 53 and extends along the flat portion of the bottom 53 as indicated in Figures 3 and 4. A reinforcing beam 55 extends transversely under the bottom 53 near the portion 53a thereof. A plurality of rigidi'fyin'g ribs or struts 51 extend from the beam 56 to the reinforcing member 55.

A plate 58 extends across the top portion =of the bowl between the side walls "thereof at the front endof the bowl as shown in Figures 3 and '4. This plate 58 is secured to the side walls of the bowl and serves to rigidity these walls as well 'as'to hold the same together. The plate also acts as a closure member for the top portion of the bowl.

A second plate '59 (Figures 3 and 4) extends across the top portion "of the bowl between the side walls thereof "at the rear of the bowl. This late 5'9 rigidifies the side walls at their rear ends and also acts as a scraper to remove dirt clinging to the plate 25 when the bowl is tilted to the dumping position shown in dotted lines in Figon the main frame I!) of the scraper and are preferably pivotally connected to the front ends of the side frame beams id or the ends of the transverse beam [3 as at 63 (Figures 3 and 4).

The jacks 62 have piston rods 64 extending through their top ends. The piston rods 64 are connected at their inner ends to pistons '(not shown) slidably mounted in the jack cylinders. Fluid under pressure such as oil from a pump on the prime mover (not shown) is supplied to the lower end of the jack cylinders through a single hose 65 extendin from the prime mover. 'The hose '65 is coupled to a pipe 66 in the tongue member ll of the main frame H). The pipe 66 is joined to a transverse pipe 61 in the beam member It. The ends of the transverse pipe 6! are connected with flexible hoses '68 which are coupled to the lower ends of the jack cylinders.

Fluid under pressure such as oil from the same pump is supplied to the upper ends of the jack cylinders through a flexible hose 69 from the tractor (not shown). The hose 69 is coupled with a pipe 1B in the tongue member H. The pipe 70, in turn, is coupled with a transverse pipe H in the transverse beam Hi. The ends of the pipe H receive flexible hoses T2. The hoses 1 2 are coupled with pipes 13 extending along the jack cylinders to the top ends of the jacks as shown in Figure 2.

A single valve on the prime mover (not shown) can thus direct oil under pressure to either end of both jacks 62 for forcing the piston rods 64 out of or into the jack cylinders.

The ends of the piston rods are pivoted at M to the pivot bosses 6B. The pivotal connection between the piston rods 6'4 and the scraper bowl '58 through the bosses 60 is above and ahead of the pivotal connection between the bowl and the frame 2| when the bowl is in carrying position as shown in Figure 3.

As best shown in Figure 2, flexible cables having clevises 16 at their forward ends are pivoted to the bosses (ill. The rear ends of the cables 15 have clevise's ll thereon pivoted to the upper arms of bell cranks 18. As best shown in Figure 4, each bell crank 18 is pivotally mounted as at 19 between the plates 25 and 21 0f the frame member 2 l The upper arms of the bell crank 18 receiving the clevi'ses ll extend through slot's such as provided in the top of the frame member 2 I.

The lower arms of the bell cranks 18 are connected through links such as 8! (Figures 4 to 7) with ears 82 (Figures 4 and 6) provided on the shaft 20. Clevises 83 and 8t join the links 8| with the bell cranks l8 and ears 82 respectively. If desired, one pair of clevises such as the clevises 84 can be adjustable along the length of the links 8! to vary the effective lengths of the links.

When the hydraulic jacks 62 are operated to lower the front end of the bowl 50 to scraping position by supplying fluid under pressure to the top ends of the jacks for forcing the piston rods 64 into the jack cylinders, the cables 15 are tightened because the pivot bosses 66 to which they are connected move away from the frame member 2| as best shown in Figure 4. This causes the cables to pull the upper arms of the bell cranks l8 forwardly and thus move the lower arms of the bell cranks upwardly. Such action causes the links 8| to act against the shaft and thus compress the springs 22 whereupon the frame 2| will be lowered as shown in dotted lines in Figure 4. This lowering of the frame 2! of course, lowers the pivotal connections 49 with the scraper bowl from the level designated by the line XX to the level designated by the line YY in Figure 4. The entire scraper bowl 53 is thus lowered and the bottom 53 thereof is maintained in substantially horizontal position.

Since the scraper blade 54 is in advance of the bottom 53 of the bowl, this bottom will not drag against the ground because of the cuts made by the scraper blade.

When the jacks 62 are operated to raise the front end of the scraper bowl by forcing fluid into the bottoms of the jack cylinders and thereby moving the piston rods out of the cylinders, the bowl will pivot about the pivot points 49 and the clevises 16 will move toward the bell cranks 18. The springs 22 will then expand to move the frame member 2! upwardly. Such upward movement of the frame member will, of course, raise the pivot points for the bowl back to the level XX shown in Figure 4 and the bowl will be carried in spaced relation from the ground.

A continued movement of the bowl into the dumping position as shown in Figure 3 in dotted lines will merely serve to further slacken the cables 75. The dirt collected in the bowl 5!! during the scraping operation is thus dumped out of the open rear end of the bowl between the portion 53a of its bottom and the plate 25 of the frame member 2i. The beam 26 of the frame member will serve to level the discharged load as the scraper is moved forwardly. The plate 59 will serve to scrape dirt clinging to the plate 26 so that the entire contents of the bowl will be discharged.

From the above description it should be understood that, during load-carrying and dumping positions the bottom of the scraper bowl is in spaced relation above the ground level. However when the front end of the bowl is tilted to scraping position, the entire bowl settles downwardly at a somewhat slower rate than the rate of movement of the forward end of the bowl. The bottom of the bowl is thus maintained at a substantially horizontal position during scraping operations and, in any event, is at a less incline than was heretofore possible.

A front end gate 90 is provided for the scraper bowl 50. This gate 90 is provided with rearwardly extending arms 9| pivoted to the side walls of the scraper bowl at points ahead of the bowl supporting pivots 49. The gate is arcuateshaped in conformity with the front end contour of the bowl and serves to close the space beneath the plate 58 and the scraper blade 54 during load-carrying operations.

However, as the bowl is lowered to scraping position the gate 9!] must be held above the scraper blade 54 so that dirt can enter into the bowl. For this purpose a shoe 92 is pivoted on the transverse beam I3 of the main frame as best shown in Figures 3 and 4. A pivotal connection 93 joins the bottom of the shoe 92 with the beam 13.

A toggle rod 94 is pivotally connected at its forward end with ears 95 formed on the shoe 92. The rod 94 is slidable through a housing 96 pivoted on the beam I3. A helical spring 9'! is mounted around the rod 94 between the housing 96 and a collar 98 formed on the rod.

The spring 91 thus urges the rod forwardly to move the shoe 92 against the gate 90.

A reinforcing beam 98a is welded on the gate transversely across the top thereof. Since the shoe 92 is urged against the gate 90 it will abut the beam Qua whenever the gate is lowered sufficiently to bring the beam into contact with the shoe. A further lowering of the bowl will then move the scraper blade 54 beneath the bottom of the gate as ShOWn in dotted lines in Figure 4,

The toggle arrangement for the gate 92 is desirable since the gate is of a curved contour.

As the bowl 50 is raised, from a scraping position to a load-carrying position, the front end thereof is automatically closed by the gate. A further raising of the front end of the bowl will bring stops 99 (Figure 2) projecting from the front of the bowl adjacent the lower portion of the plate 58 into contact with abutment plates Hi0 carried at the top of the gate. The stops 99 will thus carry the gate with the bowl as the bowl is tilted to dumping position shown in dotted lines in Figure 3.

The rear end of the bowl is thus automatically closed during scraping and load-carrying positions by the plate 26 of the frame member 2!. The front end of the bowl is automatically closed during load-carrying and dumping positions by the gate 90.

Likewise the rear end of the bowl is automatically opened when the bowl is tilted to dumping position by moving the bottom of the bowl away from the plate 26. In addition, the front end of the bowl is opened when the bowl is lowered into scraping position by operation of the shoe 92 against the beam 9041 on the front gate 90.

As shown in Figures 5 and '7, brackets lfll are bolted to the side plates 25 of the frame member 2| for supporting stop pins [02. The pins I02 are adapted to abut against the shaft 20 to hold the frame member 2| from being lowered beyond a desired maximum. The pins I02 are slidable in the brackets Hll so as to project beneath the brackets at desired lengths. Bolts Hi3 hold the pins in adjusted relation in the brackets.

In the modification shown in Figures 8 and 9, parts identical with parts described in Figures 1 to '7 inclusive have been designated by the same reference numerals. In this modification, however, the vertically movable frame 2| is supported from the main frame by means of a pair of fluid pressure operated jacks l M. The jacks H0 have the cylinders H! thereof pivoted to lugs I I2 welded on the shaft 20. The pistons H3 of the jacks H0 have bosses IM formed on the tops thereof. Pins H5 extend through the bosses I I4 and through ribs such as I I6 and i I! provided between the beams 23 and 24 at the back of the plate 26 of the frame 2 I.

Fluid under pressure is supplied to the jack cylinders III through the bottom thereof by means of a supply line I I8. The supply line may communicate with the bottom of the tilting jacks 62 as shown in Figure 8, or may be directly connected with the pipe line for supplying fluid to the bottom of the tilting jacks 62.

A valve I20 is mounted in the supply line H8.

As best shown in Figure 10, the Valve I28 comprises a housing I2I defining an inlet chamber I22 for receiving the supply line I I3 from one of the tilting jacks .52.

The housing I2I also defines a discharge chamber I23 receiving that portion of the supply line I-I8 leading directly to a jack cylinder I I I.

A port I24 joins the chambers I22 and I23. This port is closed by a poppet valve I25 mounted in the discharge port I23 and held against the mouth of the port. I24 by means of a light spring I216. Any other suitable check valve construction can be used.

A relief chamber I21 is also provided by the housing I2 I. This relief chamber receives a slidable relief valve I28 therein. A spring I29 urges the valve I28 against a seat I36 formed around a second port I3I joining the chambers I22 and I23.

A pressure screw I32 is provided for adjusting the compression of the spring I 29.

The jacks I I9 have pistons I I3 therein that are materially larger in diameter than the pistons in the tilting jacks 62. They will therefore lift the same load at lower fluid pressure than the tilting jacks but will not move as quickly as the tilting jacks. However, the cable I5, bell crank I8 and link connections 8| function to hold the frame 2! down when the bowl is in scraping position so that the loads on the jacks III] are increased. In this manner the flexible link connections act as an equalizer to distribute the loads between the lifting jacks H9 and the tilting jacks v62, thereby causing them to function simultaneously. Thus when the large diameter pistons H3 are held down by the linkconnections and fluid pressure .is then applied to the bottoms of the pistons in the tilting jacks .62for tilting the bowl upwardly fromscr-aping position the large diameter pistons I I3 will act thru the linkage connections with the bowl to assist in the tilting operation.

.When fluid under pressure is admitted into the lowerends of the tilting jacks 62 to raise the forward end of the bowl from scraping position, the fluid will be forced through the valve I20 into the jack cylinders III. This fluid is maintained in the cylinders III by the valves I25 and I28.

Stops can be provided in the jacks III) to preventthe pistons I I3 from rising above this level or-thestraps-32 can abut against the shaft 2!! to limit the upward travel of the pistons II3.

When fluid under pressure is admitted to the top-ends of the tilting jacks 62 the pressure in-the bottom ends of the jacks is released. However the valve I25 prevents fluid in the jack cylinders I from draining out of the cylinders until the piston rods 64 of the tilting jacks 62 take up the slack in the cables 15 and operate the bell cranks 18 to pull the frame member 2| downward. This downward pull, of course, acts on the fluid in the jack cylinders III and gradually builds up the pressure of the fluid in the jack cylinders until it is sufficient to force open thevalve I28. The fluid willthen bleed through the valveback into the return line. The pivot points 49 ofthe bowl 5.0 will thus be lowered to settle the bottom of the bowl. The respective diameters of the pistons in the cylinders IIII and tilting jacks B2 are regulated so as to operate at proper timed relation to each other and at desired relative speeds. 'Ihus the larger diameter pistons I13 in the jacks I II) do not move as far or as quickly as the pistons in the tilting jacks 62, because they only regulate the level .of the bowl pivot points whereas the tilting jacks function to tilt the bowl about its pivot points.

In both modifications of the invention the front end of the bowl is tilted at a higher rate than the rate of raising and lowering the rear end of the bowl. This prevents a dragging of the bot-,- tom of the bowl against the ground.

In further alternative embodiments of the invention the vertically movable frame 2| or rear end gate 2I can be operated by an independently controlled raising and lowering device. Thus a pair of lifting jacks such as III) could be controlled from a separate valve on the tractor or pulling implement. Likewise, extensible means such as springs for supporting the frame or gate could be contracted or released to raise and lower the frame or gate by independent cable connections operated from the tractor. In theseembodiments the level of the pivotal supports for the bowl andthe height of the bottom of the gate from the ground can be adjusted without use of the tilting jacks.

The arrangements of this invention provide for maintaining the dirt receptacle-of a scraper at a minimum tilt during scraping operations and at the same time function to produce a desired clearance between the bottom of the bowl and the ground level during all positions of the dirt receptacle.

The bottoms of the dirt receptacles, according to this'invention, may be maintained at a desired incline irrespective of the depth of cut .made by the scraper by mere adjustment in the link connections.

I am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated .by the prior art.

I claim as my invention:

1. A scraper comprising a main frame, a scraper bowl, resilient means between the frame and bowl for supporting the bowl from the frame in tiltable relation thereto, means for tilting the bowl relative to the frame, and means controlled by the tilting means for flexing the resilient means to lower the bottom of the bowl as the bowl is tilted into scraping position.

'2. A wagon scraper comprising a main frame, vertically movable means carried by the main frame, a scraper bowl pivotally connected to said vertically movable means and means for raising and lowering said vertically movable means in a single vertical plane extending transversely of said main frame in response to variations in position of the front end of the bowl.

3. A scraper comprising a main frame having spaced opposed side frame beams, wheels supporting said side frame beams from the ground, a transverse shaft extending between the side frame beams and carried by said side frame beams, a vertical rear wall member disposed over said'shaft, extensible means supporting said wall member from the shaft, an open-ended scraper bowl disposed between said side frame beams in front of said wall member, means pivotally connecting the bowl to the wall member, fluid pressure means for tilting the bowl about said pivotal means, and means for contracting said eX- tensible means to lower the wall member and pivot supports for the bowl as the fluid pressure means are operated to tilt the bowl into scraping position whereby the bottom of the bowl will be lowered into close relation to the ground.

4. A scraper comprising a main frame having spaced opposed side frame beams, a rigid transverse member carried by the side frame beams at the rear ends thereof, a plurality of extensible devices mounted on said transverse member, a vertical rear-end gate supported on said extensible devices, a side member carried on each side of the gate extending forwardly between the side frame beams, an open ended scraper bowl between the side frame beams pivoted on the side members, the rear end of the bowl being closed by the gate during scraping and load-carrying positions of the bowl, means for tilting the bowl about its pivot point to raise and lower the front end thereof and devices controlled by said means for contracting the extensible devices as the bowl is lowered to scraping position for lowering the gate and bowl relative to the frame and thereby decrease the slope of the bottom of the bowl.

5. A scraper comprising a main frame having spaced opposed side frame beams, vertical posts carried by said side frame beams, a transverse support carried by the main frame and extending transversely between the side frame beams at the rear ends thereof, a vertically movable rear end gate between said side frame beams, extensible devices carrying said gate from said transverse member, vertical tracks formed at the top of said gate on the sides thereof, slides carried by said posts engageable in said tracks for holding the gate in vertical position, said gate having side members extending forwardly therefrom between the side frame beams, a scraper bowl pivotally mounted on said side members and adapted to be closed at the rear end thereof by said gate, fluid pressure devices for tilting the bowl about its pivot points, and devices controlled by the fluid pressure devices for contracting the extensible means as the bowl is lowered into scraping position.

6. A scraper comprising a main frame, means supporting said frame from the ground, a vertically movable rear end gate carried by said main frame, a scraper bowl pivotally mounted on said gate, fluid pressure means carried by said main frame, said fluid pressure means having piston rods connected to said bowl for tilting the bowl about its pivot points, and means controlled by the fluid pressure means for lowering the rear end gate relative to the frame when the bowl is tilted into scraping position whereby the bottom of the bowl will be maintained in substantially horizontal position.

7. A wagon scraper comprising a main frame having spaced opposed side frame beams, axle structures secured on each of said side frame beams, wheels rotatably mounted on said axle structures supporting the main frame from the ground, an open ended scraper bowl mounted between the side frame beams, a vertically movable member resiliently carried by said main frame between the side frame beams, pivotal connections between the vertically movable member and scraper bowl, said vertically movable memher having a plate adapted to close the rear end of the bowl, a pair of fluid pressure jacks on said main frame, each of said jacks having a piston rod cooperating with a side of the scraper bowl to tilt the bowl relative to the frame, and a flexible link connection between the sides of the scraper bowl and the resilient means for compressing said means when the bowl is lowered into scraping position, to thereby lower the rear end of the scraper bowl.

8. A wagon scraper comprising a main frame including spaced opposed side frame beams, Wheels rotatably supporting the side frame beams from the ground, vertical posts at the ends of the side frame beams, a transverse member extending between the side frame beams at the rear ends thereof, a frame member including side plates and an arcuate front wall, springs supporting said frame member from the transverse member between the side frame beams, a track carried by the side plates of the frame member, means carried by the vertical posts slidable in said track to hold the frame member in vertical position, a scraper bowl mounted between the side frame beams, means pivotally connecting the sides of the scraper bowl with the side plates of the frame member, a pair of fluid pressure jacks mounted on said main frame, piston rods extending from said jacks, means pivotally connecting the piston rods to the sides of the scraper bowl for tilting the bowl about its pivot points, flexible means connected with the side walls of the scraper bowl, bell cranks pivotally mounted on the frame member near the top thereof, means joining the other ends of the flexible means with the bell cranks, links joining the bell cranks and the transverse member and means for supplying fluid under pressure to each of the jacks for operation of the piston rods into and out of the jack cylinders, said flexible means adapted to operate said bell cranks to compress the springs for lowering the frame and bowl when the piston rods are moved into the jack cylinders.

9. A wagon scraper comprising a main frame including spaced opposed side frame beams, wheels supporting said side frame beams from the ground, an open ended scraper bowl disposed between the side frame beams, a rear end gate supported from said side frame beams in vertically movable relation thereto, helical springs interposed between the gate and side frame beams, pivot connections between said rear end gate and said scraper bowl, means for tilting said scraper bowl relative to the side frame beams and devices operated by said means to respectively compress and release the helical springs as the bowl is moved into and out of scraping position.

10. In a wagon scraper including a main frame, a rear end gate mounted on said main frame for vertical movement relative thereto, a scraper bowl pivoted to said rear end gate, means for tilting said scraper bowl about its pivot point and means for lowering the rear end gate and scraper bowl as the bowl is tilted into scraping position.

11. A wagon scraper including a frame having spaced opposed side beams and means for supporting the frame from the ground, a scraper bowl having side walls and a bottom wall disposed between said side frame beams, a gate be tween said side frame beams for closing the rear end of the bowl, springs supporting said gate from said main frame, pivot connections between said gate and the sides of the scraper bowl, a pair of fluid pressure operated jacks on said frame for tilting said bowl relative to said frame and devices operated by said jacks forcompressing said springs to lower the gate for dropping the bottom of the bowl when the front end of the bowl is lowered into scraping position.

12. A scraper including a main frame having spaced opposed side frame beams and wheels supporting said frame beams from the ground, a rear end gate carried by said frame at the rear ends of the side frame beams in relatively movable relation thereto, an open ended scraper bowl disposed between the side frame beams, means pivotally supporting said bowl from said gate and means for raising the front end of the bowl to move the bottom of the bowl away from the gate for discharging material in the bowl beneath the gate whereby said gate acts to level off the discharge load as the scraper is moved forwardly.

13. In a scraper having a main frame including side frame beams and a scraper bowl disposed between the side frame beams, the improvement which comprises a vertically movable rear end gate supported by said side frame beams,, said gate pivotally supporting the scraper bowl, a front end gate pivoted to the scraper bowl, means for tilting the bowl relative to the rear end gate and main frame, means for lowering the rear end gate and scraper bowl relative to the frame when the front end of the bowl is tilted into scraping position and means carried by the mainframe to hold the front end gate above the bottom of the bowl when the bowl is tilted into scraping position.

14. A scraper including a main frame having spaced opposed side frame beams, a rear end gate supported by said side frame beams, an open ended scraper bowl disposed between the side frame beams for tilting movement relative thereto, said open rear end of the bowl adapted to be closed by said gate during load carrying and scraping positions of the bowl and a transverse member extending across the open end of the bowl to remove material from the gate as the bowl is tilted into dumping position.

15. In a wagon scraper including spaced opposed side frame beams and an open ended scraper bowl mounted between said side frame beams, the improvement which comprises a rear end gate carried by the side frame beams and adapted to be moved perpendicularly therefrom, and pivotal connections between said rear end gate and the scraper bowl for supporting the bowl in pivotal relation to the side frame beams.

16. In a wagon scraper of the class described including spaced opposed side frame beams and a transverse supporting member extending between the side frame beams at the rear ends thereof, the improvement which comprises a rear end gate mounted for vertical movement relative to said supporting means and a plurality of helical springs compressed between the rear end gate and the supporting member for resiliently carrying the gate relative to the side frame beams.

1'7. A scraper comprising a main frame having spaced opposed side frame beams, a scraper bowl between said frame beams, vertically movable pivot supports for said bowl carried by said frame, a fluid pressure jack on each side of the main frame connected with a side of the bowl for tilting the bowl about its pivot supports, the same ends of said jacks being in fluid intercommunication to equalize pressures within the jacks and devices controlled by operation of said jacks to raise and lower the pivot supports relative to the main frame whereby the bowl is -effectively suspended to prevent twisting thereof when the main frame is twisted, due to the automatic equalization of pressures in the jacks causing relative movement of the jacks and pivot supports.

18. A wagon scraper comprising a main frame having spaced opposed side frame beams, a bowl mounted between said side frame beams, a rear end gate for said bowl, fluid pressure jacks carrying said gate for vertical movement relative to said side frame beams, pivots connecting the gate with the sides of the scraper bowl for supporting the bowl, means for tilting the bowl about its pivot points and means for operatingsaid jacks to raise and lower the gate and bowl in accordance with variations in position of the front end of the bow.

19. A scraper comprising amain frame having spaced opposed side frame beams, a bowl between said side frame beams, a fluid pressure jack construction carried from said side frame beams, a pair of pivot supports for said bowl supported by said jack construction, said pivot supports connected with said bowl for tiltably carrying the bowl relative to the frame, a tilting fluid pressure jack construction interposed between the frame and bowl for tilting the bowl relative to the frame, means establishing fluid communication between the jack constructions to cause the first mentioned jack construction to raise the pivot supports when the tilting jack construction raises the front end of the bowl from scraping position, and a device for lowering the pivot supports when the tilting jack construction lowers the front end of the bowl into scraping position.

20. A scraper comprising a main frame, a pair of supporting fluid pressure jacks carried from said frame, a pair of pivot supports carried by said jacks, a scraper pivoted to said supports, a pair of tilting fluid pressure jacks carried by the main frame and connected to the scraper for tilting the scraper about its pivot supports, means establishing fluid communication between the supporting jacks and tilting jacks, a check valve in said means for retaining fluid in the supporting jacks, a relief valve in said means for bleeding fluid out of the supporting jacks, and devices controlled by the tilting jacks to lower the pivot supports whereby increased fluid pressure in the supporting jacks will open the relief valve.

21. A scraper comprising a main frame having spaced opposed side frame beams, a scraper bowl between said side frame beams, a shaft extending transversely between the rear ends of the side frame beams, a pair of jack cylinders supported on said shaft and extending upwardly therefrom, relatively large diameter pistons slidable in said cylinders, a rear end gate connected to said pistons, means pivotally connecting the bowl and the gate, a tilting jack cylinder mounted on each side of the main frame, relatively small diameter pistons slidable in said cylinders and connected with the sides of the scraper bowl, a fluid supply line communicating with the same ends of both tilting jack cylinders for operating the pistons therein to raise the front end of the bowl, supply lines feeding fluid from said first mentioned supply line to the bottoms of the jack cylinders on the shaft, check and relief valves in said supply lines and flexible means operated by the tilting jacks to lower the rear end gate when the front end of the bowl is lowered to scraping position to force the large diameter pistons into their cylinders whereby fluid will flow out of said cylinders through the relief valve and whereby an operation of the tilting jacks to raise the bowl from scraping position will force fluid past the check valve to raise said large diameter pistons as soon as the flexible means are loosened.

22. A scrap-er including a main frame, hydraulic supporting jacks carried by said frame, a rear end gate supported by said jacks, a scraper bowl pivoted to said gate and supported thereby, hydraulic jacks on said frame for tilting the bowl, and oil connections between the tilting and supporting jacks to effect a raising of the gate and bowl when the bowl is tilted up from scraping position.

23. A scraper comprising a main frame, extensible means carried by said frame, a rear end gate supported on said extensible means, a scraper bowl pivotally supported by said gate, means for contracting the extensible means when the bowl is tilted into scraping position for lowering the gate and bowl close to the ground and adjustable stops on said gate to limit the degree of lowering of the gate and bowl.

24. In a scraper having a main frame including side frame beams and a scraper bowl disposed between the side frame beams, the improvement which comprises a vertically movable rear end gate supported by said side frame beams, said gate pivotally supporting the scraper bowl, a front end gate pivoted to the scraper bowl, means for tilting the bowl relative to the rear end gate and main frame, means for lowering the rear end gate and scraper bowl relative tothe frame when the front end of the bowl is tilted into scraping position, a shoe pivoted to the main frame, means urging said shoe against said front end gate, and an abutment on said gate for engaging said shoe whereby the shoe will hold the gate in spaced relation from the bottom of the bowl as the front end of the bowl is lowered into scraping position.

25. In a scraper having a main frame including side frame beams and a scraper bowl disposed between the side frame beams, the improvement which comprises a vertically movable rear end gate supported by said side frame beams, said gate pivotally supporting the scraper bowl, a front end gate pivoted to the scraper bowl, means for tilting the bowl relative to the rear end gate and main frame, means for lowering the rear end gate and scraper bowl relative to the frame when the front end of the bowl is tilted into scraping position, an abutment member carried by said front end gate, a shoe pivoted to the main frame, and spring means urging the shoe against said gate, said shoe adapted to abut said member as the bowl is lowered to scraping position.

26. In a scraper including a main frame, a rear end gate structure mounted on said frame for movement relative thereto, a scraper bowl pivoted to said rear end gate structure, means for tilting the said scraper bowl about its pivot point, and means for lowering the rear end gate structure and scraper bowl as the bowl is tilted into scraping position.

27. In a scraper including a main frame, a rear end gate structure mounted on said main frame for movement relative thereto, a fluid pressure jack operatively connected between said main frame and said rear end gate structure to raise and lower the gate structure relative to the main frame, a scraper bowl pivoted to said rear end gate structure, means for tilting the bowl about its pivot point, and means for operating said fluid pressure jack to raise and lower the gate structure and bowl in accordance with variations in position of the front end of the bowl.

28. In a scraper including a frame, a scraper bowl, bowl mounting means carried by said frame and pivotally supporting said bowl, means for tilting said bowl relative to the frame to raise and lower the front end of the bowl between carrying and scraping position, means controlled by the tilting means for lowering the bowl mounting means and bowl when the bowl is tilted into scraping position to settle the bottom of the bowl close to the ground and provide a flat digging angle and means for raising the bowl mounting means and bowl when the bowl is tilted into carry position to provide clearance between the bottom of the bowl and the ground.

HARRY I-I. WASHBOND. 

